Field of the Invention
This invention relates to a method of manufacturing microscopic elements or microelements and an apparatus for carrying out the same. More particularly, this invention is directed to a method of manufacturing magnetic microelements such as magnetic microdevices and magnetic quantum devices, and an apparatus for manufacturing such magnetic microelements.
A technique of manufacturing microelements has been developed particularly in the field of semiconductor. In a typical known method of manufacturing microelements, after forming a thin film of about 0.1-2 .mu.m thickness on a substrate by evaporation or CVD method, a part of the thin film is removed by electron-beam lithography, photolithography or electron-beam drawing method to form a microelement having a desired configuration or pattern.
On the other hand, since the concept about the magnetic integrated circuit has been proposed in the field of magnetic materials, various types of research have been carried out in an attempt to improve a resolving power of magnetic structures by means of ultramicro fabrication technique. To this end, in addition to the above mentioned electron-beam drawing method, micro-lithography, a lift-off method, argon-ion-milling and the like have been adopted in the ultramicro fabrications of magnetic elements.
The electron-beam drawing method requires not only complex and expensive equipment such as a plasma CVD equipment, electron-beam lithography equipment, and focused ion-beam equipment, but also large scale equipment such as a clean room, mask aligner and the like.
In the micro-lithography, a microscopic pattern, i.e. micropattern or nano-pattern is directly formed in a resist film applied on a surface of a material to be processed, and therefore such a process could not be practically applied in mass production on a commercial base.
Also in the lift-off method, a process could not be performed in a depth direction, and thus it could not be applied to the manufacture of magnetic microelements such as a thin film magnetic head, micro-inductor and magnetic microdevice which require a relatively large thickness.
Since the argon ion-milling does not utilize a chemical reaction, its processing speed could not be higher than a difference between a milling rate for a mask material and a milling rate for a material to be processed. Furthermore, a cross sectional configuration of a processed material is liable to be trapezoid, so that the formation of microelements is restricted.